I did install all binaries, and there is no errorr messages related to
postinst.
There is a test to check if the restorecon binary from policycoreutils is
present or not preventing the error to show up if it is not installed.

2016-02-19 0:48 GMT+01:00 Andres Rodriguez <email address hidden>:

> Here's the output of installing without Recommends (and coreutils):
>
> roaksoax@unleashed:~$ lxc exec xenial6 -- /bin/sh
> # sudo apt-get install isc-dhcp-server --no-install-recommends
> Reading package lists... Done
> Building dependency tree
> Reading state information... Done
> The following additional packages will be installed:
>   libirs-export91 libisccfg-export90
> Suggested packages:
>   isc-dhcp-server-ldap apparmor
> Recommended packages:
>   policycoreutils
> The following NEW packages will be installed:
>   isc-dhcp-server libirs-export91 libisccfg-export90
> 0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded.
> Need to get 483 kB of archives.
> After this operation, 1,718 kB of additional disk space will be used.
> Do you want to continue? [Y/n] y
> Get:1 http://archive.ubuntu.com/ubuntu xenial/main i386 libisccfg-export90
> i386 1:9.9.5.dfsg-12.1ubuntu1 [21.7 kB]
> Get:2 http://archive.ubuntu.com/ubuntu xenial/main i386 libirs-export91
> i386 1:9.9.5.dfsg-12.1ubuntu1 [18.5 kB]
> Get:3 http://archive.ubuntu.com/ubuntu xenial/main i386 isc-dhcp-server
> i386 4.3.3-5ubuntu5 [443 kB]
> Fetched 483 kB in 1s (405 kB/s)
> Preconfiguring packages ...
> Selecting previously unselected package libisccfg-export90.
> (Reading database ... 12764 files and directories currently installed.)
> Preparing to unpack
> .../libisccfg-export90_1%3a9.9.5.dfsg-12.1ubuntu1_i386.deb ...
> Unpacking libisccfg-export90 (1:9.9.5.dfsg-12.1ubuntu1) ...
> Selecting previously unselected package libirs-export91.
> Preparing to unpack .../libirs-export91_1%3a9.9.5.dfsg-12.1ubuntu1_i386.deb
> ...
> Unpacking libirs-export91 (1:9.9.5.dfsg-12.1ubuntu1) ...
> Selecting previously unselected package isc-dhcp-server.
> Preparing to unpack .../isc-dhcp-server_4.3.3-5ubuntu5_i386.deb ...
> Unpacking isc-dhcp-server (4.3.3-5ubuntu5) ...
> Processing triggers for libc-bin (2.21-0ubuntu6) ...
> Processing triggers for ureadahead (0.100.0-19) ...
> Processing triggers for systemd (229-1ubuntu2) ...
> Setting up libisccfg-export90 (1:9.9.5.dfsg-12.1ubuntu1) ...
> Setting up libirs-export91 (1:9.9.5.dfsg-12.1ubuntu1) ...
> Setting up isc-dhcp-server (4.3.3-5ubuntu5) ...
> Generating /etc/default/isc-dhcp-server...
> Processing triggers for libc-bin (2.21-0ubuntu6) ...
> Processing triggers for ureadahead (0.100.0-19) ...
> Processing triggers for systemd (229-1ubuntu2) ...
> # dpkg -l | grep policy
> ii  libsemanage-common        2.3-1build2                  all
>  Common files for SELinux policy management libraries
> ii  libsemanage1:i386         2.3-1build2                  i386
> SELinux policy management library
> # dpkg -l | grep policycoreutils
>
> On Thu, Feb 18, 2016 at 6:28 PM, Robie Basak <email address hidden>
> wrote:
>
> > Downgrading to Medium, as I feel that Critical needs a justification.
> >
> > ** Changed in: isc-dhcp (Ubuntu)
> >    Importance: Critical => Medium
> >
> > --
> > You received this bug notification because you are subscribed to the bug
> > report.
> > https://bugs.launchpad.net/bugs/1546358
> >
> > Title:
> >   policycoreutils (in universe) is installed by default by isc-dhcp-
> >   server as it is a Recommends
> >
> > To manage notifications about this bug go to:
> >
> >
> https://bugs.launchpad.net/ubuntu/+source/isc-dhcp/+bug/1546358/+subscriptions
> >
>
>
> --
> Andres Rodriguez (RoAkSoAx)
> Ubuntu Server Developer
> MSc. Telecom & Networking
> Systems Engineer
>
> --
> You received this bug notification because you are a bug assignee.
> https://bugs.launchpad.net/bugs/1546358
>
> Title:
>   policycoreutils (in universe) is installed by default by isc-dhcp-
>   server as it is a Recommends
>
> Status in isc-dhcp package in Ubuntu:
>   New
>
> Bug description:
>   Policycoreutils is being installed by default because the package is
>   listed as a Recommends. This package, however, is in universe and
>   seems to be pulling selinux. This should not be a recommends but
>   rather, it should be a Suggests.
>
>   It seems that the postinst requires a binary being shipped in
>   policycoreutils:
>
>   debian/isc-dhcp-server.postinst:test ! -x /sbin/restorecon ||
>   /sbin/restorecon /var/lib/dhcp/dhcpd.leases
>
> To manage notifications about this bug go to:
>
> https://bugs.launchpad.net/ubuntu/+source/isc-dhcp/+bug/1546358/+subscriptions
>